• Journal of Dairy Science and Biotechnology
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• 제36권3호
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• pp.178-185
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• 2018

Kefir, which originates in the Caucasian mountains, is a cultured milk beverage produced by a combination of acidic and alcoholic fermentation. Kefir products are commonly used as food vehicles to deliver health-promoting materials including kefran and lactic acid bacteria to consumers. The aim of this study was to develop a freeze-dried starter culture without yeast and assess the suitability of kefir-like dairy products for the growth of lactic acid bacteria and the acidification of milk. Pasteurized whole milk (SNF 8.5%) stored at $25^{\circ}C$ was aseptically inoculated with starter cultures (0.002% w/v); it was kept at $25^{\circ}C$ until the pH attained a value of 4.6. Ten grams of the kefir-like product sample was diluted with 90 mL of 0.15% peptone water diluent in a milk dilution bottle, followed by uniform mixing for 1 min. Viable cells of Lactobacillus species were enumerated on modified-MRS agar (pH 5.2), with incubation at $37^{\circ}C$ for 48 h. Viable cells of Lactococcus species were enumerated on M17-lactose agar, with incubation at $32^{\circ}C$ for 48 h. The pH attained a value of 4.6 after fermentation for 9 h 30 min (Starter 1), 9 h 45 min (Starter 2), and 12 h (Starter 3). The viable cell count of Lactobacillus sp. and Lactococcus sp. was initially $10^5{\sim}10^6CFU/g$; it increased significantly to $10^9CFU/g$ after 12 h of incubation. During the storage of the kefir-like products at $4^{\circ}C$ for 1 4 days, the total viable cell numbers were unchanged, but the pH decreased slightly. The consistency of the kefir products increased gradually during the storage. The organoleptic properties of the kefir products fermented using the new starter culture are more desirable than those of commercial kefir. These results suggest that the newly developed starter culture without yeast could be suitable for kefir fermentation.

• 한국미생물·생명공학회지
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• 제28권2호
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• pp.117-123
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• 2000

P. phosphoreum의 생존과 생체발광도는 온도에 의해 많은 영향을 받는다. 냉동 저장한 세포의 경우 glycerol의 보호 작용으로 세포농도와 생균수는 측정기간 동안 일정하게 유지된 반면 생체발광도는 glycerol 첨가 직후 급속히 감소하였으며, 저장 이후에도 감소된 생체발광도가 활성화되지 못하였다. 최적 생육온도인 $20^{\circ}C$의 경우 저장 초기 세포가 성장함에 따라 세포수의 증가를 보였으나 일정 시간 이후 세포 분해 현상으로 인하여 생균수 및 세포 집락수의 감소를 나타내었으며, 생체발광도는 저장 3일 이후 소멸되었다. 이와는 대조적으로 $4^{\circ}C$에 저장한 세포의 생체발광도는 저장 10일 동안 지속되어 가장 높은 생체발광 유지도를 나타내었으나 장기간 저온 저장으로 인하여 세포가 VBNC 상태에 돌입됨에 따라 총균수와 생균수는 일정한 반면 저장 10일 이후 세포 집락수의 급격한 감소를 나타내었으며, 저장 20일 이후 간균에서 구균으로 세포 형태상의 변화를 나타내었다. 이에 따라 세포 저장 시 접종원의 농도를 달리하여 VBNC 상태와 생체발광도의 관련성을 조사한 결과 VBNC 세포가 증가할수록 생체발광도의 감소를 나타내었다. 따라서 VBNC 세포를 감소시키기 위하여 세포를 고정화하여 저장한 결과 별도의 활성제 없이 실온에서 다시 활성화되어 고정화하지 않은 세포에 비해 2.3배 높은 생체발광유지도를 나타내었으며, 저온저장에 따른 platebility 소실과 세포 응축현상이 나타나지 않았다. 이러한 결과는 세포의 고정화 방법을 이용하여 $4^{\circ}C$에서도 세포의 생존 및 생체발광 유지도를 향상시킬 수 있으며, 동결 건조법의 단점을 보완해 줄 것으로 생각된다.

• 농업과학연구
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• 제13권1호
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• pp.130-138
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• 1986

즉석에서 이용할 수 있는 생고추의 파쇄 제품을 개발하기 위한 기초자료를 얻기 위하여 생고추를 파쇄한 후 밀봉함에 있어서의 첨가물질, 포장재료, 저장온도 및 기간이 제품의 품질 성분에 마치는 영향을 검토하여 다음과 같은 결과를 얻었다. 1. 파쇄한 생고추에 15%의 Sodium chloride를 첨가하면 Sodium chloride 무첨가구에 비하여 산도, Capsanthin 및 Capsaicin 잔존량 면에서 효과가 현저하였다. 2. 파쇄한 생고추의 밀봉 저장에는 Polyethlene film 보다 Polyvinylidene chloride film이 효과적이었다. 3. 파쇄한 생고추를 Polyvinylidene chloride film으로 밀봉 저장할 정우 Capsanthin의 분해는 온도가 높을수록 심하였고 Capsaicin의 분해는 저장 초기에 빨랐으며 Sodium chloride 첨가에 의하여 현저하게 저하하였다. 4. 저장중에 있어서 Vitamin C의 분해는 저온에서 보다 고온에서 심하였고 Sodium chloride 첨가에 의하여 상당히 억제되었다. 5. 저장중의 총균수 및 젖산균수의 증가는 Sodium chloride 첨가에 의하여 크게 억제되었고 저장온도에 따르는 차이는 거의 인정되지 않았다.

• 한국식품저장유통학회지
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• 제22권5호
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• pp.666-673
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• 2015

본 연구에서는 항암 등의 기능성이 우수한 것으로 알려진 개똥쑥 추출물을 첨가하여 김치를 제조하여 김치 품질특성 변화를 살펴보았다. 개똥쑥의 물 또는 70% 에탄올로 추출물 1 또는 2% 첨가하여 김치를 제조하고 10, $15^{\circ}C$에서 20일간 숙성하면서 pH, 산도, 환원당, 생균수 및 젖산균수의 변화 및 관능조사를 하였다. 개똥쑥의 첨가여부와는 관계없이 pH, 산도 환원당, 생균수 및 젖산균수는 저장 4~6일까지 증가하고 이후 완만히 증가하는 경향을 보여 개똥쑥 추출물이 김치 품질에 미치는 영향은 크지 않은 것으로 나타났으며 개똥쑥 추출물 첨가 김치의 적정 숙성온도 및 기간은 $10^{\circ}C$에서 10일간이었다. 관능검사의 경우 맛, 향 등의 기호도에서 전반적으로 개똥쑥 물 또는 에탄올 추출물 1%를 첨가하여 제조하는 것이 좋았으나 개똥쑥 물 또는 에탄올 추출물 2%를 첨가한 김치는 쓴 맛과 검은 색 등으로 인해 기호도가 떨어진 것으로 나타났다. 따라서 개똥쑥 물 또는 에탄올 추출물은 김치 제조에 1%를 김치 제조에 첨가하는 것이 적당한 것으로 사료된다.

• 한국포장학회지
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• 제28권1호
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• pp.67-73
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• 2022

The food cold chain refers to a technology and distribution supply chain applied to maintain a constant temperature suitable for the product from production (harvest) to delivery to consumers. In particular, in Korea, the insulation material used in the food cold chain is mostly EPS (Expanded Polystyrene), which is used as a transport container for various food cold chains. However, according to the government's eco-friendly policy, companies charge environmental contributions to the use of EPS, but due to its low price and convenience of handling, it is still used as a container for delivering food. In this study, in order to measure the domestic delivery environment of general refrigerated foods, changes in impact, temperature, and humidity during transport of the EPS packaging system containing foods and ice pack refrigerants were measured. As a result, there were 2?3 sections in which a high impact force of 40 G or more was generated during transport. This can cause damage to the product and EPS container. The difference in temperature and humidity changes by parcel transport routes is more than 30%, so it is necessary to present accurate standards for the domestic cold chain distribution environment. As a result of microbial experiments. the transportation period had a dominant effect on the increase in total viable count and E. coli count.

• Asian-Australasian Journal of Animal Sciences
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• 제31권4호
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• pp.522-528
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• 2018

Objective: This study evaluated inclusion of buckwheat silage to the diet of growing lambs in terms of meat quality as compared to maize silage. Methods: Buckwheat, rich in total phenols (TP, 33 g/kg dry matter [DM]), was harvested at the end of the milk stage and ensiled in 40 kg plastic bags after wilting (294 g/kg silage DM). A total of 18 growing lambs ($21.6{\pm}1.2$) were individually fed isonitrogenous and isoenergetic total mixed rations (TMR) for 75 d that either contained buckwheat or maize silage at DM proportions of 0.50. At the end of feeding trail all lambs were slaughtered to assess carcass characteristics and meat quality. Results: Buckwheat silage increased (p<0.01) the DM intake of lambs as compared to maize silage, but had no effects (p>0.05) on live weight gain and feed efficiency. Carcass weight, dressing percentage, meat pH, water holding capacity, cooking loss, shear force ($kg/cm^2$), and total viable bacteria count of meat did not differ (p>0.05) between the treatments. However, TP content of meat increased (p<0.001) by feeding buckwheat TMR. Feeding buckwheat TMR also decreased (p<0.05) the b* values of meat. Conclusion: The results provide that buckwheat silage is palatable and could successfully include TMR of growing lambs with no adverse effects on performance, carcass and meat quality. Additionally, feeding buckwheat silage to lambs offers increased TP in meat.

• 한국산업융합학회 논문집
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• 제25권1호
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• pp.11-19
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• 2022

This study provided basic data for the commercialization of healthy functional beverages by examining the physicochemical characteristics, nutrient content, and microbiological safety of onion peel beverage. The total acid of onion peel beverage was 0.12 mg/g and the pH was 6.07. According to the storage period, the total acid decreased and the pH increased in all temperature ranges(25℃, 35℃, and 45℃). After 30 days of storage, it showed 0.06 mg/g in all temperature sections and maintained the pH 7 range. The total phenol content, which is a nutritional component of onion peel beverage, was 0.93 mg/g, flavonoid content was 0.25 mg/g, and quercetin content was 0.17 mg/g. The flavonoid content decreased according to the storage period, and in the case of storage temperature of 25℃, it contained 50% content up to 120 days of storage, but in the case of 35℃ and 45℃, it had a flavonoid content up to 90 days and 30 days, respectively. In the case of quercetin, a residual rate of about 50% was shown for 150 days of storage at 25℃ and 35℃. In the case of 45℃, it decreased to 35% at 30 days of storage. On the other hand, onion peel beverage maintained a viable cell count of less than 5 CFU/mL for 150 days of storage, and no coliform group was detected. As a result of analyzing the quality characteristics of onion peel beverage according to storage period, quality stability was confirmed in physicochemical characteristics and microbiological safety. Research on changes in biological activity according to low-temperature distribution or storage period is necessary.

• Asian-Australasian Journal of Animal Sciences
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• 제13권9호
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• pp.1323-1328
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• 2000

Bovine colostrum, which contains a large quantity of immunoglobulins, is indispensable for newborn animals. The establishment of a new procedure for preserving colostrum without losing the immunological activity is significant. We examined the effect of high hydrostatic pressure treatment (100~500 MPa) on the preservability and the immunochemical activity of bovine colostrum. When high hydrostatic pressure treatment was 300 MPa or more, the increase of the total viable count, coliforms and psychrotrophic gram-negative bacteria was suppressed effectively. In particular, the number of coliforms in colostrum treated at 300 MPa or more hardly increased for 35 days at $4{^{\circ}C}$. At 400 MPa or more, both gelling of the colostrum and denaturation of immunoglobulins were observed. However, if the pressure was 300 MPa, immunoglobulins were scarcely influenced and the neutralizing titers against the bovine coronavirus did not decrease. Therefore, it was suggested that 300 MPa was the best pressure for good preservability of colostrum without reducing the immunochemical response.

• 한국미생물·생명공학회지
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• 제20권2호
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• pp.219-224
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• 1992

식염농도 3로$15^{\circ}C$에서 발효시킨 물김치에서 젖산균과 효모의 균수변화를 측정한 결과 숙성기까지 효모의 수가 증가한 후 후기에 감소하는 것으로 나타났으며 숙성적기에 효모를 분리동정한 결과 Saccharomyuces sp.가 24주로 대부분을 차지하였으나 Kluyveromyces fragilis 3주, Torulopsis candida 2주도 발견되었다. 이 중에서 S.saitoanus Y17, S.capensis Y29, S.chevalieri Y13, K.fragilis Y2, T.candida Y9를 같은 김치에서 분리한 젖산균 Lactobaccillus plan tarum Lp2, Pediococcus pentosaceus P1, Leuconostoc mesentroides Lu5와 각각 혼합배양하여 효모와 생육에 미치는 영향을 조사한 결과 모두 생육이 억제되었으며, 이는 lacti acid나 H2O2에 의한 억제가 아닌 다른 물질에 의한 것으로 밝혀졌다. 이 세 종류의 젖산균에 의해 영향을 받는 정도는 효모의 종류에 따라 매우 큰 차이를 나타내었다.

• 한국식품영양과학회지
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• 제27권2호
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• pp.259-267
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• 1998

Typical characteristics of Mejus must be understood to get the basic data for setting up mass production system of traditional fermented soybean products. One hundred and twenty one Mejus were collected from various places and analyed. Most of shapes were rectangular and some were spherical, conical, cylindrical and doughnut types. The weight of Mejus was 0.4~4.2kg. Chemical analysis showed: moisture content, 9.73~58.22% ; pH, 4.95~8.15; acidity, 0.6~3.8% ; soluble protein content, 4.45~12.31%; soluble sugar content, 0.82~10.95%. Enzyme assay showed: $\alpha$-amylase activity, 5.0~874.2 units/g; $\beta$-amylase activity, 0.02~27.74units/g; acidic protease activity, 31.3~225.1unts/g; lipase activity 1.0~53.0units/g. Total viable cells were 3.72$\times$107~1.35$\times$1010cfu/g, and yeast and mold count 6.46$\times$104~8.91$\times$106cfu/g. respectively. $\alpha$-Amylase activity of a traditional Meju from Incheon showed the highest activity of 732.8 units/g(interior section) and 823.2units/g (exterior section). $\beta$-Amylase activity was the highest{3.57 units/g (interior sectin) and 4.25units/g (exterior section)} in Meju from Chunbuk. Acidic protease activity was the highest in sample from Seoul, whereas traditional Meju from Kyongnam showed the highest activity of 21.5units/g(interior section) and 37.5units/g(exterior sectin).